This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Our long term goals are to elucidate biopolymers molecular structures, especially polysaccharides, and their interactions with solvent and solute molecules and the synergistic interactions in mixed polysaccharides towards gaining insights about their structure-function relationships. In this regard, the main thrust of this proposal is centered on determining the three-dimensional structures of a number of biologically important and industrially useful polysaccharides. Our ongoing study will include, but not limited to (as need arises), the specimens from algal (iota, kappa and lambda carrageenans);bacterial (gellan analog and cepacian);fungal (glucuronoxylomannan);plant (rhamnogalacturonan);wood (galactoglucomannan) and a binary system (bacterial xanthan:plant glucomannan and bacterial acetan:plant glucomannan). Further, we are in the process of exploring the use of polysaccharide fibers as possible drug carriers. In this regard, initially, carrageenan fibers complexed with some known small molecules will be tested towards obtaining crystalline diffraction patterns and delineating the drug-carrageenan interactions. These polysaccharides or polysaccharide complexes have an inherent tendency to form helical structures with only limited lateral ordering and are not amenable for growing single crystals. Hence, fiber diffraction is the only method of choice for visualizing their three-dimensional organization. Such structural information is essential towards understanding their interactions with solvent and solute molecules as well as with other polysaccharides for their effective utilization in food and pharmaceutical applications. The results will further highlight the conformational space available to polysaccharides as they occur in glycosaminoglycans and cellular walls.